This invention relates generally to the field of recycling rubber containing materials, and more particularly to an apparatus for processing rubber vehicle tires, effecting a separation of the various constituent materials comprising such tires, facilitating reclamation and recycling of said materials and obtaining usable crumb rubber.
Various studies show that approximately seventy-eight percent of used vehicle tires still end up in landfills or are illegally dumped. Vehicle tires held in stockpiles have trapped water through exposure to the elements, which provides an ideal habitat for disease carrying mosquitoes and rodents; and vehicle tires buried whole in landfills have fueled tire fires.
Portions of recycled tires, especially the rubber portion, when separated into crumb rubber, can be used as a fuel source, a component of asphalt paving mixtures and as extenders in a variety of thermoplastic or elastomeric products such as roofing materials, walk pads, carpet and flooring underlay, sport surfaces, and other products. Vehicle tires typically consist of reinforcing metallic layers, fabric layers, and rubber containing materials. To obtain usable crumb rubber for the above referenced uses, the metallic layers must be separated from the rubber containing materials.
Many of the methods currently used to recycle vehicle tires require precutting, followed with grinding of the tires. These methods use large amounts of power, create wastewater streams, cause wear and tear on the grinding apparatus, and do not completely separate the metallic layers from the rubber components. Information relevant to attempts to address these problems can be found in U.S. Pat. Nos. 5,683,038; 5,482,215; and 5,675,882. However, each one of these references suffers from one or more of the following disadvantages: use of large amounts of power, whether to power the machinery or to provide pressure to water jets, and use of one or more cutting type apparatus. Additionally, U.S. Pat. No. 5,611,492 requires precutting of the tires and the use of energy to power both microwave and vacuum to complete recovery of the rubber crumb.
As the market for crumb rubber grows exponentially, new, better and more economical methods for obtaining crumb rubber without creating additional burdens on the environment are necessary, which the instant invention provides.
A primary object of the present invention is to reduce the time, energy, and effort spent in recycling vehicle tires. Another object of the present invention is to recycle scrap tires to produce a separation of the rubber material from the metallic constituents of said tires. Another object of the present invention is to ease the burdens scrap tires place on the environment by use of environmentally friendly solvents and lessen the amount of energy used in the recycling process.
These objects and others are achieved in the present invention which provides a method and an apparatus for processing scrap rubber vehicle tires and, by means of soaking said tire in an environmentally friendly solvent to soften the tire, making the tire more malleable, applying direct pressure to the tire to force the tire against a rotatable grater surface which separates the components of the tire, allowing the shredded rubber components to pass through the grater surface for further work, leaving behind the fabric and metallic constituents which are moved from the grater surface off the crescent shaped table and discarded or subjected to further processing.